Antagonism of Host Antiviral Responses by Kaposi's Sarcoma-Associated Herpesvirus Tegument Protein ORF45
Figure 2
Induction of IFN signaling by KSHV soluble KSHV K8.1 glycoprotein but not by KSHV virions.
Subconfluent 293T cells grown in 24-well plates were transfected with pGL-IFNA1 (a luciferase report vector driven by the IFNA1 promoter), an IRF-7 expressing plasmid (pCR3.1-IRF-7) cloned into a pCR3.1 vector and a pRL-TK reporter (Renilla luciferase as an internal control) plasmid. At 24 h post-transfection, cells were infected with the indicated viruses at the indicated MOI or treated with purified soluble KSHV K8.1 or gB glycoproteins at increasing concentrations of 1 and 5 µg/ml, respectively. Six hours following infection, cell lysates were prepared and activation of the IFNA1 promoter transcription was evaluated using a dual luciferase assay kit.